Invisible Bullet-Magnetism Aim Assistance in VR Dart Throwing: Effects on User Experience and Performance

Aim assistance has been shown to be effective in traditional video games; however, its application in VR contexts remains relatively underexplored. We investigate the effects of invisible bullet-magnetism aim assistance applied at the time of throw on performance and user experience in a VR dart-throwing task. We corrected the trajectory by adjusting the initial throwing direction to reduce the landing position deviation from the target center by 50%. We conducted a within-subjects experiment with 29 participants, comparing the aim-assist condition with a control condition without assistance. Aim assistance with invisible bullet magnetism significantly improved objective and perceived performance, accuracy, and precision. Participants in the aim-assist condition reported significantly higher perceived competence and control, while perceived suspense and pressure were scored significantly lower. Enjoyment, internal attribution of achievement, and workload remained comparable between the two conditions. Participants attributed their success to themselves rather than external factors in both conditions. The invisible bullet-magnetism aim assistance in our study remained largely unnoticed, and participants favored the aim-assist condition.